Tape actuated multiple contact switch



Sept. 22, 1964 M. R. CARTELL.: 3,150,242

TAPE ACTUATED MULTIPLE CONTACT SWITCH Filed Nov. 29, 1961 2 Sheets-Sheet 1 Sept. 22, 1964 M. R. cAR'rELLl TAPE ACTUATED MULTIPLE CONTACT SWITCH 2 Sheets-Sheet 2 Filed Nov. 29, 1961 INVENTOR. ffm/'M5L RA :Afm-u United States Patent O 3,159,242 TAPE AETUATED CNTAQT Sil/ETES Michael l. Cartelli, @tl-23 99th St., Corona 63, NKY. Filed Nov. 29, i951, Ser. No. 155,742 i3 21. Zilli-46) This invention relates to switches, particularly to multiple contact switches, and especially motor operated switches.

The general object of the present invention is to improve switches for selection or programming or sampling or other such purpose requiring complex switching of multiple contacts.

The present switch employs a loop of insulation tape with rectangular holes through which contact is made. A more particular object is to provide a switch mechanism which may be standardized, except for the tape and a so-called circuit hoard, by changing which the switch may be used for a great number and variety of contact arrangements.

Still another object or" the invention is to provide such a switch which is unusually compact. In one embodiment, not much larger than a two-inch cube, there is an array of ninety-six contact brushes 'which may be connected with as many as forty-eight outside connections. In accordance with one feature and object of the invention, this desired compactness is further aided by mounting the motor and its associated reduction gearing inside the loop of tape.

La accordance with another feature and object of the invention, the switch terminates in an array of many pins for the brushes and for the outside connections, all of which may be detachahly received in a connector base resembling the female half of a detachable connector. Thus the switch is readily plugged into or removed from the connector base, without disturbing the complex wiring to that base. This makes it easy to service the switch, including also any desired change of the tape, or of the circuit board. By having a spare available there is almost no down time because the unit can be replaced instantly.

As previously mentioned, the switch may be standardized except for the circuit board and tape, but if desired an additional change which may be made is in the terminal plate, the many holes through which may be iilled or not lled by the aforesaid contact brushes and terminal posts, and similar remark applies to the connector base which may have either a full or partial set of female contacts, as required by the number of pins on the terminal plate. This depends on manufacturing economy and the importance of standardization in a particular manufacturing plant.

To accomplish the foregoing objects, and other objects which will hereinafter appear, the invention resides in the switch elements and their relation one to another as are hereinafter more particularly described in the following specification. The specication is accompanied by drawings in which:

FIG. l is a side elevation of a switch embodying features of the invention;

FTG. 2 is a plan view of the switch removed from its connector base and looking toward the array of pins on the terminal plate of the switch;

FIG. 3 is a section taken approximately in the plane of the line 3-3 of FIG. 2, and drawn to enlarged scale, with some connector base contacts omitted to simplify the drawing;

FIG. 4 is a horizontal section taken approximately in the plane of the stepped line 4 4 of FIG. 3;

FIG. 5 is a transverse section taken approximately in the plane of the line 5 5 of FIG. 3;

3,15%,242 Patented Sept. 22, 19554 FCice FIGS. 5A and 5B show details drawn to enlarged scale;

FlG. 6 is a perspective view explanatory or" the relation of the circuit board to the contact brushes and the posts;

FIG. 7 illustrates one way to arrange the contact lines and cross lines of the circuit board when providing eight outside connections;

FIG. 8 is a similar View showing one possible arrangement of contact lines and cross lines when providing sixteen outside connections;

FlG. 9 illustrates a piece of tape slotted for use as programming tape; and

FlG. l0 illustrates a piece of tape slotted for use as a sampling or scanning tape. v

Referring to the drawing, and more particularly to FIGS. l and 3, the switch comprises an endless loop of insulation tape 12. There is also a motor 14, which in the present case is a rotary solenoid stepper motor with reduction gears 16 and it, the latter turning a sprocket wheel 29 which engages a line of sprocket holes in the tape, in order to move the same. A fragment of tape is shown at l2 in FIGS. 4, 9 and 10, and the sprocket holes are indicated at 22. It will be seen in FIGS. l and 3 that the motor and reduction gearing and sprocket wheel are located inside the loop of tape l2, thus making the unit compact.

Rererring to FIGS. 3 and 5, the switch includes an insulation circuit board 24 which is mounted inside the loop l2 and in contact therewith. There is also an insulation terminal plate 26 which is mounted outside the loop, and which is approximately coextensive with the board 24. The board has printed conductive Contact lines on the side of the board against which the tape runs. These lines are shown at 28 in FIG. 5, there being eight such lines in the present case. The lines are also indicated at 28 in FIG. 4, and are symbolized by single lines in FIGS. 7 and 8. They usually extend longitudinally of the tape but may extend transversely of the tape. in some switching combinations where several lines are connected together, they may be printed as a single large surface, but for convenience I refer to them as lines.

T he circuit board also has printed conductive lines on its opposite side, these lines extending transversely of the tape and usually being stepped in length, as symbolized at 3% m FIG. 7. The circuit board 24 is wider than the tape, thus providing marginal portions which are located outside the tape, and the cross lines terminate in the marginal portion.

The contact lines and cross lines are connected at appropriate intersections, preferably by metal lined apertures indicated at 32 in FIG. 5. This construction is shown drawn to larger scale in FIG. 5A. At their outer ends the cross lines also terminate in metal lined holes indicated generally at 34 and 36 in FIGS. 7 and 8, it being understood that only the used holes need be metal lined.

Referring now to FlGS. 3 and 5, the terminal plate 26 has an array of resilient contact brushes 4i) carried by pins 42 passing through and secured in the terminal plate 2d, as by the provision of iiutes or ribs 44. As will be seen from inspection of the drawing, the contact brushes are aligned with the longitudinal conductive lines 28 of the circuit board, and also with the slots or windows cut. through the tape 3 2.

The terminal plate 26 also has posts along either or both marginal portions, and in the present case there are four rows of such posts, the outer rows 46 having twelve posts, and the inner rows 4S having thirteen posts. The two extra end posts thus provided are used for wire connections to the driving motor 14, and insofar as the switching operation is concerned, there are four rows of twelve posts each, or forty-eight posts in all. However,

Va support and guide for the loop 12 of tape.

r, D not Vall of these need be used, and in FIG. 7 eight of the posts are being used, while in FIG. 8 sixteen posts are being used. In the simple form shown in FIG. 6, contact line 28 is connected to the outside by'a cross line 34) and a marginal post 54 at the outer end of cross line 30. As is perhaps best shown in FIG. 5, the innerend of each post is'bifurcated, as shown at 50, so that it may be resiliently and removably received in a mating one of the metal lined holes shown at 34 or 36 in FIGS. 7 and V8.

Referring now to FIGS. 1 and 3, there is also a connector base 52 having an array of female contacts 64 dimensioned to receive the pins 42 of the brushes, and also to receive the outer ends 54 of the posts, for external connection. As will be seen by comparison of FIGS. 3 and 5, or FIGS. 1 and 2, the switch with its pins and posts is bodily detachable from the connector base 52 without any need for disturbing thecomplex wiring which may be connected to the outer ends of the female contacts 64 of the connector base 52.

The motor 14 is received in a body 69 of aluminum which acts as arheat sink for the motor. The body 6i) may be split as shown at 62, and provided with a clamping screw 65 disposed transversely. When the screw 65V is loose, the motor may be slid into position in the body 6i), and then by tightening the screw 65 the motor is clamped in position. v

The aluminum body 69 is so shaped that it also acts as The body 60 may be considerably narrower than the switch, and it is preferably' provided at two corners with rigid cross bars 66which make up for the full width of the switch. The bars 66 have threaded holes to receive four vassembly screws 68 located at the corners of the switch. These screws pass through the corners of the terminal plateV 26 and through the corners of the circuit board 24, and are received in the ends of the cross bars 66. AsY shown in FIG. 5, the terminal plate 26 is thickened somewhat at 7 il, 'these being the marginal portionsof the terminal plate disposed longitudinally of and outside the edges of the tape l2, thus making it possible for the assembly screws to clamp the, terminal plate and the circuit board 24 tightly against the bars 66. The increased thickness Vat the marginal portions 70 provides clearance for free passage of thetape betweenthe circuit board and the terminal board. Y

In addition, the terminal plate is deeply hollowed over an extensive area, indicated at 72 in FIGS. 3 and 5. The deep recess or chamber thus provided houses the contact brushes 40 previously referred to. The contact brushes are preferably formed integrally with their pins 42 and are supported thereby. The-surface of the terminal plate has three levels. One is that of the two marginal portions 70 which are clamped tightly against the circuit board 24.

Another is that through .which the tape runs, it being a rectangular frame around the third or deeply recessed surface for housing the brushes. The said frame is wide on three sides and narrow on the fourth, which is the side remotefrom the sprocket holes.

The tape may be made of any suitable insulation material, but is preferably made of Mylar because of its high insulation property, it having a breakdown voltage of 4000 volts per 0.001 inchof thickness, compared, for example,.to air, with a breakdown voltage of about 40 volts per 0.001 inch. It also has great strength and a wide range of service temperature. The sprocket'holes may be punched in accordance with standard motion picture film practise at a pitch of say, 3)/16 inch. However, in the particular example of switch here shown the travel for each step is 1/s inch, and the sprocket wheel therefore is so related to the motor by the reduction gears i6 and 18 as to move the tape only of a sprocket hole pitch.

The'brushes 40 and pins 42 Vare preferably made of Y beryllium copper and are preferably made integral One method is to use round rod for the pins and to coin a portion of the rod to form the desired flexible brush. An-

other and preferred method is to employ thin sheet material which is rolled up by the action of a progressive die to form the pins, while a portion is left flat to form the brush. Berylluim copper has the advantage that it may be worked while soft, and hardened later. Thek combined Vbrush and pin may be force inserted into the insulation terminal plate, or it may be arranged for insertion with a snap fit, or the pins maybe used as mold inserts when molding the terminal plate.

The circuit board 24 and terminal plate 26 'are' preferably made of a reinforced phenolic laminate, or epoxy glass laminate. The printed lines on the circuit board may be copper and made in accordance with conventional printed board techniques. It may be noted that there is no metal-to-rnetal abrasion or wear, the traveling element being the Mylar tape. However, the contacts are continuously cleaned because of the wiping actionof the tape itself as it runs between the contact brush and the printed line.

In the present case there may be twelve brushes along each printed line, and with eight printed lines there may be ninety-six'brushes in all. They are spaced 1/8 inch apart longitudinally of the tape so that for one cycle the tape length is 1%. inches. The total length of the endless band should be an integral multiple of this distance, and in the present case the tape is four cycles long, or six inches long. For more elaborate programming a much greater length of tape could be provided, with the extra tape stored in convolutions in an adjacent magazine, but

Vfor many purposes the tape Vas here illustrated is long enough.

`fthere a slot in the tape is to be very long it may be bridged at intervals by short bridges of tape, and two adjacent brushes may be connected together and used as a single or common brush, thus maintaining contact even during the passage of the bridges, the latter being narrower than the spacing between the brushes.

To complete the protective'housing of the switch a generally rectangular, drawn sheet metal cover Sil is employed. This is dimensionedV to rit over the tape loop and `around the periphery of the terminal plate 26. It is detachably secured to the latter by four small screws indicated by 82 in FIG. 4. Y.

The friction of the large number of pins inserted in the connector base is adequate for most mounting purposes, but when the switch is to be used in special situations of Vibration or shock, the mounting may, if desired, be supplemented by the provision of latches or locks, such as thumb screws, between the switch `and the connector base to hold them against undesired separation. Such supplemental lock means are already well known in connection with detachable connectors. v

in FiGS. 7 and 8 the cross lines run to the inner posts.

When more than twenty-four, say ya maximum of fortyeight, cross lines are needed, they run to the outer as well as the inner posts, and in such case the printed lines must be quite narrow when the switch is made as compactly as here shown. if wide printed lines are wanted, an additional printed board may be employed as a lamination above the circuit board shown, for the express purpose of providing additional cross lines, and theposts are made long enough to make contact with the upper cross lines.

For someV purposes the stepping motor may be of the homing type, that is, thev motor has an interrupter and steps repeatedly to a specified position, and then stops.

In still otherY cases the motor may be a continuously running motor, preferably of the synchronous type.

In preferred form the switch is motor operated, and in most cases is remotely controlled, and thus may be considered to act as a kind of relay. However, many features of the invention are valuable even with manual operation, and a simple push button or lever may be used, which in turn steps the film along, either by means of a ratchet wheel and a sprocket wheel as shown, or by direct areas/ia El engagement of a manually operated claw with the sprocket holes. The same complex switching is obtainable, and the same advantage of great flexibility by changing only the tape and circuit board.

ln the drawing the switch has been shown in inverted position, but it will be understood that it may be used in any position. lt may he plugged into the connector base from above as well as below, or sideward when used on an upright panel.

One advantage of this switching arrangement is compactness. The common and distributing contacts may be placed very close to each other without loss or" dielectric strength, because the film-tape material may be chosen to give the desired dielectric strength, even though thin. Also, the switch employs a rectangular grid layout for the flexible contacts, which is a most compact rrangement. Thirdly, die switch allows many sets of contacts to be set on one deck, and all of these contacts may be led out of the switch in close proximity to each other, where they may be used as a soldering header, or preferaoly as a detachable connector, with the aid of the mating connector base, as here illustrated. This eliminate" the need for the provision and connection oi a separate connector, thus reducing size and weight and installation or manufacturing cost. With less soldering there is an increase in reliability.

Another advantage is simplicity, because the number or" moving parts is greatly reduced compared to other presently used designs. Only two wire connections are required (for the motor), because all the switch terminals lead directly out of the package without need for internal wiring within the switch itself. A minimum of metal to metal rubbing occurs with this design, which increases the life ot' the unit. The contacts, both common and distributing contacts, are cleaned by the interaction of metal on metal when a circuit is made or broken,

by the sliding of the tape past the contacts.

rThere is low electrical noise from the contacts. This is due to the means of making and breaking electrical contact, because the contacts move toward one another, without travelling one along the other, and the parts are stationary during the dwell period. This is particularly important when low voltages are being passed.

The switch is ilexible in use. With 95 brushes and outside connections it will be seen that the switching possibilities are enormous. The particular switching mechanism described above may he employed as a multiple-pole multiple-throw switch. The posts correspond to the poles, and the brushes correspond to the throws. By appropriate perforation of the tape and appropriate printing of the lines on the circuit board, the switch may range all the way from a forty-eight-pole double-throw to a twopole forty-eight-throw switch, the product of the poles and throws being ninety-six.

The circuit board of FIG. 7 would provide an eightpole twelve-throw switch, and the circuit board or FIG. 8 would provide a sixteen-pole six-throw switch. With such arrangements the switching cycle is completed in one passage or less of vthe circuit board, by the tape.

With less than eight poles a travel of the tape greater than the circuit board may be required, and thus with four poles, and twenty-four throws, two sections of tape pass the circuit board before repeating the cycle. Various layouts may be employed, but in general one section of tape would have perforations cooperating with halt" lthe contact lines, and the next section would have perforations cooperating with the other half of the contact lines, and the contact lines would be connected in pairs, and to four posts.

For a two-pole fory-eight-throw switch the entire length of tape here shown would be employed, there being only two pertorations and two contact lines effective at any one time, and four Contact lines being connected together for one pole, and the other four being connected together for the other pole of the two-pole switch. In the switch to Q here illustrated the tape is four times the length of the circuit board, and therefore is adapted to provide a twopole forty-eight-throw Switch, but for a single-pole ninetysix-throw switch it would be necessary to provide a tape loop double the length of that shown.

A desirable feature of the present switch is that odd arrangements may be employed without necessitating shipping positions, or dead stops, such as are necessary when using a rotary switch. For example, for an eightpole nine-throw switch, a rotary switch having twelve positions would have three dead positions corresponding to positions lill, l1 and l2. before starting the cycle again. ri`he present switch will begin a new cycle without dead stops by appropriately perforating the tape. However, in some cases the length of the complete tape loop may have to be modified to provide an integral number of cycles, and in such cases spacers may be added to accommodate and to support the resulting tape of somewhat different length.

Moreover, the switch may be used for programming, and for this purpose a very much longer tape may be used, if necessary, depending on the cycle time and the desired resolution. Perforations may -be elongated for sustained contact, and there is no limit to the length of each perforation, because long perforations may be bridged, as explained above. For programming the motor may he a constant speed or synchronous motor, rather than a stepper motor, or a stepper motor may he employed and actuated by a periodic electrical pulse, with the pulse-to-pulse time being determined by the resolution desired in the programming and by the cycle time. The advantage of an interrupted instead of a continuous drive is that it decreases the make or break time in switching; that is, it provides a fast malte or break, and thereby increases the switching capacity o the contacts.

The switch also may be used as a sampling or scanning switch. This arrangement may be produced by shorting all common contacts or lines of the circuit board (or by using one large area of metal), and staggering the perforations in the tape, and moving the tape at a speed dependinfy on the number of positions to be sampled per second.

The number of circuits to be sampled determines the design of the circuit board and the tape. As a maximum this switch could sample ninety-six circuits, but then using a tape twelve inches long instead of six inches as here shown. With the siX inch tape here shown forty-eight circuits may be sampled, and in fact, there could be two such sampling systems, each sampling forty-eight circuits, within the capacity of the switch and short tape as illustrated. The perforations in the tape would be the same as for a two-pole forti -eight-throw switch, but the motor would probably be run continuously for scanning which implies a constant rate, whereas sampling implies the use of an irregular rate, and switching implies that the motion may not only be irregular, but at long intervals.

It is believed that the construction and method of use of my improved switch, as well as the advantages thereof, will be apparent from the foregoing detailed description. It will also be understood that while I have shown and described the invention in a preferred form, changes may be made in the structure shown without departing from the scope of the invention as sought to be dened in the following claims. ln the claims the reference to contract lines is not intended to exclude an area where several lines are anyway to be electrically connected together. in the claims the reference to the brushes being carried by pins is not intended to exclude a detachable construction with the contacts reversed so that the brushes are carried by female contacts while the connector base carries the pins, instead of vice versa, nor is it intended to exclude a nonetachable structure in which the brushes are carried by contacts or terminals which are adapted to receive ilexible conductors. The reference to the terminal plate being thickened at its marginal portions to f 1 Y provide clearance for sliding passage of the tape is not intended to exclude the usetof s hims or spacers for that purpose. conductors being connected at appropriate intersections is not intended ,to` require a crossed relationship but rather that the connections are at appropriate points.

I claim: Y Y Y 1. A compact switch comprisingran endlessA loop of perforated insulation tape, means to move the tape, an insulation circuit board mounted inside the loop in contact therewith, an insulation terminal plate mounted outside the loop tand approximately Vcoextensive with said board, said board having conductive contact lines on the side agm'nst which the tape runs, and having cross conductors extending transversely of the tape, said contact lines and cross conductors being connected at appropriate points, a marginal portion of said board having connection means at the ends ofy said cross conductors, said terminal plate having an array of resilient brushes carried by pins passing through and secured in said terminal plate in rows, said terminal Vplate also having posts along a marginal portion, the upper ends of said' posts mating with said connection means and thus being connected to the cross conductors and thence to the contact lines.

2. A compact switch Vcomprising an endless loop of perforated insulation tape, means to move the tape, an insulation circuit board mounted inside the loop in contact therewith, an insulation terminal plate mounted outside the loop and approximately coextensive with said board, said board having conductive contact lines extending longitudinally of the tape on the side against which the tape runs, and having cross conductors extending transversely of the tape on the opposite side of the board, said contactV lines and cross conductors being connected at appropriateV intersections,`a marginal portion of said board having connection means at the ends or" said cross conductors, said terminal plate having an array of resilient brushes carried by pins passing through and secured in said terminal plate in rows Ialigned with the longitudinal lines of the board, said terminal plate also'having posts along a marginal portion, the upper ends of said posts mating with said connection means and thus being connected to the cross conductors and thence to the Contact lines, and said board being removable and interchangeable with other boards having different lines, whereby the switch may be standardized except for the board vand the tape.

3. A compact switch comprising an endless loop of perforated insulation tape',V means to move the tape, an

insulation circuit board mounted inside the loop in contact therewith, an insulation terminal plate mounted outside the loopV and approximately coextensive with said board, said board having conductive contact lines on the side Vagainst which the tape runs, and having cross conductors extending transversely of the tape on the opposite side of the board, said contact lines and cross conductors being connected at appropriate points, a marginal portion of said board having connection means at the ends of said cross conductors, said terminal plate having an array of resilient brushes carried by pins passing through and secured in said terminal plate in rows, said terminal plate also having posts along a marginal portion, the upper ends of'said posts mating with said connection means and thus being connected to the cross conductors and thence `to the contact lines, and a connector base having an array of female contacts dimensioned to receive the pins of the brushes and the lower ends of the posts for external connection, the switch with its pins and posts being detachable from said connector base.Y

4. A compact switch comprising an endless loop of kperforated insulation tape, means to move the tape, an

The reference to the contact lines and cross i conductive cross lines extending transversely of the tape on the opposite side ofthe board, said contact lines and cross lines being connected at appropriate points, a marginal portion or said board having conductivermetal lined holes at the ends of said cross lines, saidtterminal plate having an array of resilient brushes carried by pins passing through and secured in said terminal plate in rows, said terminal plate also having posts along a marginal portion, the upper ends of said posts fitting in said lined holes and thus being connected to the cross lines and thence to the contact lines.

5. A compact switch comprising an endless loop of perforated insulation tape, means to move the tape, an insulation circuit board mounted inside the loop in contact therewith, an insulation terminal plate mounted outside the loop and approximately coextensive with said board, said board having printed conductive Contact lines extending longitudinally of `the tape on the side against which the tape runs, and having printed conductive cross lines extending transversely of the tape on the opposite side of the board, said contact lines and cross lines being connected at appropriate intersections, a marginal portion of said board having conductive metal lined holes at the ends of said cross lines, said terminal plate having an array of resilient brushes carried by pins passing through and secured in said terminal plate in rows aligned with the longitudinal lines of the board, said terminal plate also having posts along a marginal portion, the upper ends of said posts lit-ting in said lined holes and thus being connected to the cross lines and thence to the contact lines, and said board being removable and interchangeable with other boards having different contact and cross lines,

whereby the switch may be standardized except for the n board and the tape. Y

6. A compact switch comprising an endless loop of perforated insulation tape, means to move the tape, an insulation circuit board mounted inside the loop in contact therewith, an insulation terminal plate mounted outside the loop and approximately coextensive with said board, said board having printed conductive Contact lines on the side against which the tape runs, and having printed conductive cross lines extending transversely of the tape on the opposite side of the board, said contactlines and cross lines being connectd at appropriate points, Va marginal portion of said board having conductive metal lined holes at the ends of said cross lines, said terminal plate having an array of resilient brushes carried by pins passing through and secured in said terminal plate in rows, said terminal plate'also having posts along a marginal portion, the upper ends of said posts fitting in said lined holes and thus being connected to the Ycross lines and thence to the contact lines, and a connector base having an array of female contacts dimensioned to receive theV pins of the brushes and the lower ends of the posts for external connection, the switch with its pinsrand posts being detachable from said connector base.

7. A compact switch comprising an endless loop of perforated insulation tape having a line ot sprocket holes, motor means including a sprocket gear engaging said sprocket holes to move the tape, an insulation circuit board mounted inside the loop in contact therewith, an insulation terminal plate mounted outside the loop and Yapproximately coextensive with said board, said board having printed conductive coitactlines on the side or the board against which the tape runs, and having printed conductive cross lines extending transversely of the tape on the opposite side of the board, said contact lines and cross lines being connected at appropriate intersections by metal lined apertures, one or both marginalportions of said board outside said tape having metal lined holes at the ends of said cross lines, said terminal plate having an array of resilient brushes carried by pins passing through and secured in said terminal plate in rows, said terminal plate also having posts alongboth marginal portions, the upper ends of Ysaid posts tting in said lined Mci;

holes and thus being connected to the cross lines and thence to the contact linesl 8. A compact switch comprising an endless loop of perforated insulation tape having a line of sprocket holes, motor means including a sproc iet gear engaging said sprocket holes to move the tape, an insulation circuit board mounted inside the loop in contact therewith, an insulation terminal plate mounted outside the loop and approximately coextensive with said board, said board having printed conductive Contact lines extending longitudinally of the tape on the side of the board against which the tape runs, and having printed conductive cross lines extending transversely of the tape on the opposite side of the board, said Contact lines and cross lines being connected at appropriate intersections by metal lined apertures, one or both marginal portions of said board outside said tape having metal lined holes at the ends of said cross lines, said terminal plate having an array of resilient brushes carried by pins passing through and secured in said terminal plate in rows aligned with the longitudinal lines of the board, said terminal plate also having posts along both marginal portions, the upper ends of said posts fitting in said lined holes and thus being connected to the cross lines and thence to the contact lines, and said board being removable and interchangeable with other boards having dillierent Contact and cross lines, whereby the switch may be standardized except for the board and the tape.

9. A compact switch comprising an endless loop of perforated insulation tape having a line of sprocket holes, motor means including a sprocket gear engaging said sprocket holes to move the tape, an insulation circuit board mounted inside the loop in contact therewith, an insulation terminal plate mounted outside the loop and approximately coextensive with said board, said board having printed conductive contact lines on the side of the board against which the tape runs, and having printed conductive cross lines extending transversely of the tape on the opposite side of the board, said contact lines and cross lines being connected at appropriate intersections by metal lined apertures, one or both marginal portions of said board outside said tape having metal lined holes at the ends of said cross lines, said terminal plate having an array of resilient brushes carried by pins passing through and secured in said terminal plate in rows, said terminal plate also having posts along both marginal portions, the upper ends of said posts iitting in said lined holes and thus being connected to the cross lines and thence to the contact lines, and a connector base having an array of female contacts dimensioned to receive the pins of the brushes and the lower ends of the posts for external connection, the switch with its pins and posts being detachable from said connector base.

l0. A switch as dened in claim l in which a motor means drives the tape, and in which the motor means is mounted inside the loop of tape.

11. A switch as dened in claim 7 in which me motor is a rotary solenoid and has gearing leading to the sprocket wheel, and in which the motor and reduction gearing and sprocket wheel are mounted inside the loop of tape for compactness.

l2. A switch as deiined in claim l in which the tape is driven by a motor which is clamped in a body of metal inside the loop, said body of metal acting as a heat sink for the motor and as a support and guide for the loop of tape.

13. A switch as defmed in claim 7 in which the motor is a rotary solenoid and has gearing leading to the sprocket wheel, and in which the motor and gearing and sprocket wheel are mounted inside the loop of tape for compactness, and in which the motor and gearing are clamped in a body of aluminum acting as a heat sink for the motor and as a support and guide for the loop of tape.

14. A switch as defined in claim l in which the tape is driven by a motor which is clamped in a body of metal inside the loop, said body of metal acting as a heat sink for the motor and as a support and guide for the loop of tape, and in which the circuit board is detachably mounted at the bottom of said body inside the loop and acts as a bottom guide for the loop, and in which the terminal plate is somewhat thickened or raised at its marginal portions outside the tape, and its said marginal portions are secured to the circuit board and body.

l5. A switch as deined in claim 7 in which the motor is a rotary solenoid and has gearing leading to the sprocket wheel, and in which the motor and gearing and sprocket wheel are mounted inside the loop of tape for compactness, and in which the motor and gearing are clamped in a body of aluminum acting as a heat sink for the rnotor and as a support and guide for the loop of tape, and in which the circuit board is detachably mounted at the bottom of said body inside the loop and acts as a bottom guide for the loop, and in which the terminal plate is somewhat thickened or raised at its marginal portions outside the tape, and its said marginal portions are secured 'to the circuit board and body.

i6. A compact switch comprising an endless loop of insulation tape having a line of sprocket holes, a rotary solenoid with gearing and a sprocket wheel for engaging the sprocket holes in the tape to move the same, a body ot metal located inside and substantially lling the loop and shaped to help support and guide the same, said motor and gearing and sprocket wheel being located inside the loop of tape for compactness, and said motor being clamped in said body of metal whereby said body acts as a heat sink for the motor.

l7. A compact switch as defined in claim l in which the resilient brushes and the pins which carry the sarne are made integrally of a single piece of conductive material.

18. A compact switch as deiined in claim 6 in which the resilient brushes and the pins which carry the same are made integrally of a single piece of beryllium copper or equivalent resilient conductive material.

Lea Nov. l5, 1949 Sabins Sept. ll, 1962 

1. A COMPACT SWITCH COMPRISING AN ENDLESS LOOP OF PERFORATED INSULATION TAPE, MEANS TO MOVE THE TAPE, AN INSULATION CIRCUIT BOARD MOUNTED INSIDE THE LOOP IN CONTACT THEREWITH, AN INSULATION TERMINAL PLATE MOUNTED OUTSIDE THE LOOP AND APPROXIMATELY COEXTENSIVE WITH SAID BOARD, SAID BOARD HAVING CONDUCTIVE CONTACT LINES ON THE SIDE AGAINST WHICH THE TAPE RUNS, AND HAVING CROSS CONDUCTORS EXTENDING TRANSVERSELY OF THE TAPE, SAID CONTACT LINES AND CROSS CONDUCTORS BEING CONNECTED AT APPROPRIATE POINTS, A MARGINAL PORTION OF SAID BOARD HAVING CONNECTION MEANS AT THE ENDS OF SAID CROSS CONDUCTORS, SAID TERMINAL PLATE HAVING AN ARRAY OF RESILIENT BRUSHES CARRIED BY PINS PASSING THROUGH AND SECURED IN SAID TERMINAL PLATE IN ROWS, SAID TERMINAL PLATE ALSO HAVING POSTS ALONG A MARGINAL PORTION, THE UPPER ENDS OF SAID POSTS MATING WITH SAID CONNECTION MEANS AND THUS BEING CONNECTED TO THE CROSS CONDUCTORS AND THENCE TO THE CONTACT LINES. 